Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/arch/mips/sgi-ip22/ip22-time.c b/arch/mips/sgi-ip22/ip22-time.c
new file mode 100644
index 0000000..173f768
--- /dev/null
+++ b/arch/mips/sgi-ip22/ip22-time.c
@@ -0,0 +1,214 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Time operations for IP22 machines. Original code may come from
+ * Ralf Baechle or David S. Miller (sorry guys, i'm really not sure)
+ *
+ * Copyright (C) 2001 by Ladislav Michl
+ * Copyright (C) 2003 Ralf Baechle (ralf@linux-mips.org)
+ */
+#include <linux/bcd.h>
+#include <linux/ds1286.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+#include <linux/time.h>
+
+#include <asm/cpu.h>
+#include <asm/mipsregs.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/time.h>
+#include <asm/sgialib.h>
+#include <asm/sgi/ioc.h>
+#include <asm/sgi/hpc3.h>
+#include <asm/sgi/ip22.h>
+
+/*
+ * note that mktime uses month from 1 to 12 while to_tm
+ * uses 0 to 11.
+ */
+static unsigned long indy_rtc_get_time(void)
+{
+ unsigned int yrs, mon, day, hrs, min, sec;
+ unsigned int save_control;
+
+ save_control = hpc3c0->rtcregs[RTC_CMD] & 0xff;
+ hpc3c0->rtcregs[RTC_CMD] = save_control | RTC_TE;
+
+ sec = BCD2BIN(hpc3c0->rtcregs[RTC_SECONDS] & 0xff);
+ min = BCD2BIN(hpc3c0->rtcregs[RTC_MINUTES] & 0xff);
+ hrs = BCD2BIN(hpc3c0->rtcregs[RTC_HOURS] & 0x3f);
+ day = BCD2BIN(hpc3c0->rtcregs[RTC_DATE] & 0xff);
+ mon = BCD2BIN(hpc3c0->rtcregs[RTC_MONTH] & 0x1f);
+ yrs = BCD2BIN(hpc3c0->rtcregs[RTC_YEAR] & 0xff);
+
+ hpc3c0->rtcregs[RTC_CMD] = save_control;
+
+ if (yrs < 45)
+ yrs += 30;
+ if ((yrs += 40) < 70)
+ yrs += 100;
+
+ return mktime(yrs + 1900, mon, day, hrs, min, sec);
+}
+
+static int indy_rtc_set_time(unsigned long tim)
+{
+ struct rtc_time tm;
+ unsigned int save_control;
+
+ to_tm(tim, &tm);
+
+ tm.tm_mon += 1; /* tm_mon starts at zero */
+ tm.tm_year -= 1940;
+ if (tm.tm_year >= 100)
+ tm.tm_year -= 100;
+
+ save_control = hpc3c0->rtcregs[RTC_CMD] & 0xff;
+ hpc3c0->rtcregs[RTC_CMD] = save_control | RTC_TE;
+
+ hpc3c0->rtcregs[RTC_YEAR] = BIN2BCD(tm.tm_sec);
+ hpc3c0->rtcregs[RTC_MONTH] = BIN2BCD(tm.tm_mon);
+ hpc3c0->rtcregs[RTC_DATE] = BIN2BCD(tm.tm_mday);
+ hpc3c0->rtcregs[RTC_HOURS] = BIN2BCD(tm.tm_hour);
+ hpc3c0->rtcregs[RTC_MINUTES] = BIN2BCD(tm.tm_min);
+ hpc3c0->rtcregs[RTC_SECONDS] = BIN2BCD(tm.tm_sec);
+ hpc3c0->rtcregs[RTC_HUNDREDTH_SECOND] = 0;
+
+ hpc3c0->rtcregs[RTC_CMD] = save_control;
+
+ return 0;
+}
+
+static unsigned long dosample(void)
+{
+ u32 ct0, ct1;
+ volatile u8 msb, lsb;
+
+ /* Start the counter. */
+ sgint->tcword = (SGINT_TCWORD_CNT2 | SGINT_TCWORD_CALL |
+ SGINT_TCWORD_MRGEN);
+ sgint->tcnt2 = SGINT_TCSAMP_COUNTER & 0xff;
+ sgint->tcnt2 = SGINT_TCSAMP_COUNTER >> 8;
+
+ /* Get initial counter invariant */
+ ct0 = read_c0_count();
+
+ /* Latch and spin until top byte of counter2 is zero */
+ do {
+ sgint->tcword = SGINT_TCWORD_CNT2 | SGINT_TCWORD_CLAT;
+ lsb = sgint->tcnt2;
+ msb = sgint->tcnt2;
+ ct1 = read_c0_count();
+ } while (msb);
+
+ /* Stop the counter. */
+ sgint->tcword = (SGINT_TCWORD_CNT2 | SGINT_TCWORD_CALL |
+ SGINT_TCWORD_MSWST);
+ /*
+ * Return the difference, this is how far the r4k counter increments
+ * for every 1/HZ seconds. We round off the nearest 1 MHz of master
+ * clock (= 1000000 / HZ / 2).
+ */
+ /*return (ct1 - ct0 + (500000/HZ/2)) / (500000/HZ) * (500000/HZ);*/
+ return (ct1 - ct0) / (500000/HZ) * (500000/HZ);
+}
+
+/*
+ * Here we need to calibrate the cycle counter to at least be close.
+ */
+static __init void indy_time_init(void)
+{
+ unsigned long r4k_ticks[3];
+ unsigned long r4k_tick;
+
+ /*
+ * Figure out the r4k offset, the algorithm is very simple and works in
+ * _all_ cases as long as the 8254 counter register itself works ok (as
+ * an interrupt driving timer it does not because of bug, this is why
+ * we are using the onchip r4k counter/compare register to serve this
+ * purpose, but for r4k_offset calculation it will work ok for us).
+ * There are other very complicated ways of performing this calculation
+ * but this one works just fine so I am not going to futz around. ;-)
+ */
+ printk(KERN_INFO "Calibrating system timer... ");
+ dosample(); /* Prime cache. */
+ dosample(); /* Prime cache. */
+ /* Zero is NOT an option. */
+ do {
+ r4k_ticks[0] = dosample();
+ } while (!r4k_ticks[0]);
+ do {
+ r4k_ticks[1] = dosample();
+ } while (!r4k_ticks[1]);
+
+ if (r4k_ticks[0] != r4k_ticks[1]) {
+ printk("warning: timer counts differ, retrying... ");
+ r4k_ticks[2] = dosample();
+ if (r4k_ticks[2] == r4k_ticks[0]
+ || r4k_ticks[2] == r4k_ticks[1])
+ r4k_tick = r4k_ticks[2];
+ else {
+ printk("disagreement, using average... ");
+ r4k_tick = (r4k_ticks[0] + r4k_ticks[1]
+ + r4k_ticks[2]) / 3;
+ }
+ } else
+ r4k_tick = r4k_ticks[0];
+
+ printk("%d [%d.%04d MHz CPU]\n", (int) r4k_tick,
+ (int) (r4k_tick / (500000 / HZ)),
+ (int) (r4k_tick % (500000 / HZ)));
+
+ mips_hpt_frequency = r4k_tick * HZ;
+}
+
+/* Generic SGI handler for (spurious) 8254 interrupts */
+void indy_8254timer_irq(struct pt_regs *regs)
+{
+ int irq = SGI_8254_0_IRQ;
+ ULONG cnt;
+ char c;
+
+ irq_enter();
+ kstat_this_cpu.irqs[irq]++;
+ printk(KERN_ALERT "Oops, got 8254 interrupt.\n");
+ ArcRead(0, &c, 1, &cnt);
+ ArcEnterInteractiveMode();
+ irq_exit();
+}
+
+void indy_r4k_timer_interrupt(struct pt_regs *regs)
+{
+ int irq = SGI_TIMER_IRQ;
+
+ irq_enter();
+ kstat_this_cpu.irqs[irq]++;
+ timer_interrupt(irq, NULL, regs);
+ irq_exit();
+}
+
+extern int setup_irq(unsigned int irq, struct irqaction *irqaction);
+
+static void indy_timer_setup(struct irqaction *irq)
+{
+ /* over-write the handler, we use our own way */
+ irq->handler = no_action;
+
+ /* setup irqaction */
+ setup_irq(SGI_TIMER_IRQ, irq);
+}
+
+void __init ip22_time_init(void)
+{
+ /* setup hookup functions */
+ rtc_get_time = indy_rtc_get_time;
+ rtc_set_time = indy_rtc_set_time;
+
+ board_time_init = indy_time_init;
+ board_timer_setup = indy_timer_setup;
+}